50L Keg Boiler Build

[hayden89]

I haven't even distilled my first wash yet, however I am already planning/starting to build a new boiler as the old stockpot and hotplate setup was just shit in the cleaning runs let alone on an actual spirit run. This new boiler will be the base to which i will eventually build a new still..... and then who knows what :shock:

I plan to run 50L keg with 2 x 2400w elements, 1" drain in the base, 4" fill/cleaning port and 4" ferrule for natural still progression from 2" reflux column to 4" bubbler.

Do i need to add a thermo to the boiler?

These are my proposed schematics for a controller. This controller will allow me to run both elements on heat up then switch to just the one controlled element during the run. I think this setup should be safe/work correctly however let me know if you can identify anything i have overlooked.

[RefluxEd]

You are using AC, not DC so the diode will allow half wave rectification to the second element at all times, so you'd not be running one element for the run, you'd have 1 and 1/2 elements. Remove the diode and you should be OK.
The SSR-25 has a total capacity of 6000 watts if mounted on a good heatsink. You'll be using 4800 watts. In most situations you should always go for a controller that has at least twice the capacity required.
I suggest you get a second SSR-25 to run the second element. That will give you plenty of headroom and will also allow you to change to more powerful elements if required. :handgestures-thumbupleft:

[Triangle]

Looks like he wants to be able to select individual elements, top one as a boost and no back feed but with both going? I assume as otherwise you wouldn't have bothered with the diode idea?

Instead of that rotary switch (though from memory I'm pretty sure they do come with a couple of extra contacts and in that case it would be fine), use a Telemechanique XB4BD33 and add 3 NO contact blocks to it. (or if the rotary allows, use 3 of the NO contacts).

In position 1 you use 1 NO to power Element 1 with SSR control.

In position 2 you use 2 NO contacts. 1 for E1, the other for E2.

In that way there is no backfeed between the elements in position 1.

[hayden89]

You are using AC, not DC so the diode will allow half wave rectification to the second element at all times, so you'd not be running one element for the run, you'd have 1 and 1/2 elements. Remove the diode and you should be OK.
The SSR-25 has a total capacity of 6000 watts if mounted on a good heatsink. You'll be using 4800 watts. In most situations you should always go for a controller that has at least twice the capacity required.
I suggest you get a second SSR-25 to run the second element. That will give you plenty of headroom and will also allow you to change to more powerful elements if required. :handgestures-thumbupleft:

Looks like he wants to be able to select individual elements, top one as a boost and no back feed but with both going? I assume as otherwise you wouldn't have bothered with the diode idea?

Instead of that rotary switch (though from memory I'm pretty sure they do come with a couple of extra contacts and in that case it would be fine), use a Telemechanique XB4BD33 and add 3 NO contact blocks to it. (or if the rotary allows, use 3 of the NO contacts).

In position 1 you use 1 NO to power Element 1 with SSR control.

In position 2 you use 2 NO contacts. 1 for E1, the other for E2.

In that way there is no backfeed between the elements in position 1.

The diode/ ac dc thing has only just clicked in my brain!! A bit of a slow moment..

What I am trying to achieve is, restrict the current from element 2 powering element 1 when the switch is in position 1 as TGS has described (hit the nail on the head).

TGS yes you are right the rotary switch has multiple NO contacts so that is what i will do.

Further reflection on this schematic finds me doubting that a single 15A input circuit will be sufficient, calculations work out to require 25A. Any thoughts on this?

Cheers for the input guys appreciate it.

[hayden89]

I have (legally) acquired a 50l keg and pulled the spear our of it. I used a gear puller to release the pressure, unscrewed the 'spear flange' and then a bit more destructive pressure on the puller to remove the flange from the inner spear.

[hayden89]

Yesterday went to 5 star and picked up, 4" SGK, 2" ferule, 2" tri clamp, 2 x 2400w elements weld type.

Today, in between Freo belting Melbourne :handgestures-thumbupleft: , I took to the keg with the angle grinder and a 4" hole saw. I also made a stand to lift the keg enough to allow for a drain in the base. The stand isnt finished yet but it is stable, strong and functional however will most probably make another one. Still need to get the 1" BSP stainless sockets for the elements and the drain fittings and then get it all welded on.

[thedarkmesh]

Looking good, keep the pictures coming!

[hayden89]

Today I sourced a few more bits for the boiler, namely, 2 x 1" SS sockets, 1 x 3/4" 90 deg bend, 1 x 3/4" SS ball valve and some caps to make an element guard.

Not happy at all with today i thought my welding skills were better than they actually are!! It didnt help that i only had limited 2mm electrodes and then had to use 2.5mm and the stick welder i have only has 2 settings 2.5 and 3.5.

Sockets cut ready for installation and drain pipe and valve mock up, propably the only bit of success today


First blow out


Patched blowout and testing for leaks


Leak test failed only slightly, so attempted to repair and failed and this is how is stands now:angry-banghead: :angry-banghead:


I will see how i go repairing the little creatures keg, however if all else fails it will be come a mash tun and i have another keg to cut up which i will get professionally welded.

[rumdidlydum]

That sucks mate. Probably should have done a practise run on the piece you cut off. Oh well we live and learn.
Nice work on the rest though :handgestures-thumbupleft:

[Camikaze]

Hey Haydo, I welded my boiler up with a stick welder too. Little tip or three to help with blowouts:

Cos your'e welding staino, the stick wont strike an arc up properly unless the amps are cranked up. Chuck your rods in the oven at 200 deg for 10 minutes, turn your amps down and strike your arc. Will strike real easy with hot sticks. Also, hit the bright metal to be welded with a blowtorch. Just cherry red mate, not raging hot otherwise warpage will occur.

Get your tolerances/gaps as close as possible with thin staino. Any slight gaps will blow out easily.

Hit up Masters/Bunnings and look for 316L 1.3mm rods. A little exxy but awesome for thin staino.

If you are still struggling, try doing small spot welds. Zap, pull off and wait till the cherry dies off, zap, pull off, zap, etc etc...:handgestures-thumbupleft: :handgestures-thumbupleft:

Cam

[hayden89]

Hey Cam,

Thanks for the feed back and the helpful advice. I will definitely use these methods to try salvage the little creatures keg.

My stick welder has 2 settings,2.5 or 3.5 which I believe should correspond with the electrode size.

I will try source some 1.3mm rods, heat then up and try zap and wait method.

Thanks again

[Camikaze]

:handgestures-thumbupleft:

[hayden89]

Finally got my keg welded.... well kind of. I took it to a friend of a friend who is a qualified welder and welds all day every day for a living. Alot of :angry-banghead: :angry-banghead: :crying-blue: and a long story short the keg is sealed with all the bits welded on however it looks like absolute shit, my stick welding on the first keg was better so this keg wont be getting polished as i was hoping to. Its still sitting on the temporary stand but elements are in, drain is plumbed and the column is fitted.

I had dramas trying get the elements to seal with the element guards however i found that thread tape worked a treat.

Did a vinegar run tonight and it took about 20mins to bring about 12l to the boil. :handgestures-thumbupleft:

[Irritable]

Hi - I'm about to start building similar to the unit in this thread. Could someone please advise as to what the whole size for the sight glass ferrule? I will be ordering soon but would like to do as much prep work as possible. I've read the heating elements require a 32mm hole, so just need the max od of the fill/sight so I can dremel the bugger.
Si

[hayden89]

Mac has all ferrule sizes detailed in this thread
viewtopic.php?f=56&t=6784&p=115889&hilit=ferrule#p115889

[Irritable]

Much appreciated, thank you.

[InglisHill]

Another trick for welding thin stainless with a stick welder is to hold the stick 30 degrees off horizontal when welding. It means the heat of the sheilding gas coming off the stick is skimming the surface of the stainless, not pointing straight into it.

[Aussiedownunder01]

Looking at your first drawing are you going to run 2+2400 elements off the single 15 am power point